基于GIS和层次分析法的海洋溢油敏感区综合等级评价体系研究

Research of evaluation index system for comprehensive sensitivity level of marine environments to oil spills based on GIS and AHP

利用层次分析法确定海洋溢油敏感区综合等级评价体系层级结构,借鉴美国海洋与大气局ESI指数原则为二级指标赋分,通过德尔菲法和层次分析法相结合的方法确定指标权重,获得海洋溢油敏感区综合等级评价函数模型。借助GIS的空间分析功能,将二级指标所对应的空间数据按照不同空间分辨率进行动态网格化编码,依据此编码获得单指标图层的赋分,结合指标权重动态生成综合评价结果网格图。该方法降低了多指标确权时权重系数确定难度,实现了海洋溢油敏感区综合等级评价。所得二级指标权重中自净能力、岸线类型和渔业价值居于权重前三位,权重之和0.47,突显了生物、生境在综合评价中的重要性。由于主要采用了主观赋权评估法,对咨询专家依赖度高。

in this study, Analytic Hierarchy Process （AHP） was used to confirm the hierarchical structure of composite grade evaluation system in marine oil spill sensitive area. The second level indexes of the system were marked as scores based on environmental sensitivity index （ESI） principal from National Oceanic and Atmospheric Administra- tion （NOAA）. The model of composite grade evaluation on marine oil spill sensitive area was established and the in- dex weight was acquired by the combination of Delphi Method and AHP. Also, the spatial data corresponded with the second level index was coded with dynamic grid, according to spatial resolution, aided by GIS. Based on the mark ob- tained through coded single index layer, the eomoosite evaluation grid graph was dynamically generated, combining with index weight. This method reduced the difficulty in determining the coefficient of index weight,during the confir- mation of multiple indexes. Tbe composite grade evaluation of marine oil spill sensitive area is realized. Self-cleaning properties,coastline and fishery were top three indexes in second level,with a total weight of 0.47. The importance of organisms and habitats were highlighted. However, as subjective assessment was applied, the system is highly depend- ent on consulting experts.